C.S. Peirce’s Pragmatism

The earliest clear statement of Peirce’s pragmatism comes from his 1878 paper "How To Make Our Ideas Clear." In this paper, Peirce introduces a maxim, or principle, which allows us to achieve the highest grade of clarity about the concepts we use. Peirce introduces this principle, which we shall discuss in detail below as the third grade of clarity, as a development of the rationalist notion of "clear and distinct ideas." Combining his pragmatic maxim with notions of clarity from Descartes and Leibniz, Peirce identifies three grades of clarity or understanding.

The first grade of clarity about a concept is to have an unreflective grasp of it in everyday experience. For instance, my inclination to keep some part of my body in stable contact with a supported horizontal surface at all times suggests that I have an underlying grasp of gravity. The second grade of clarity is to have, or be capable of providing, a definition of the concept. This definition should also be abstracted from any particular experience, i.e., it should be general. So, my ability to provide a definition of gravity (as, say, a force which attracts objects to a point, like the center of the earth) represents a grade of clarity or understanding over and above my unreflective use of that concept in walking, remaining upright, etc.

For Peirce, these two grades of clarity are only part way to a full understanding of a concept; there is a richer level of clarity. It is at this point that he introduces his own third grade of clarity. Peirce says:

Consider what effects, which might conceivably have practical bearings, we conceive the object of our conception to have. Then the whole of our conception of those effects is the whole of our conception of the object. (Peirce 1878/1992, p. 132)

On this account, then, to have a full understanding of some concept we must not only be familiar with it in day to day encounters, and be able to offer a definition of it, we must also know what effects to expect from holding that concept to be true.

For instance, a full understanding of the concept of "vinegar" comes from possessing all three grades of clarity about it. If I am able to identify vinegar and use the concept appropriately in my everyday experiences, I display the first grade of clarity about this concept. My ability to define "vinegar" as a diluted form of acetic acid, which is sharp to the taste, displays the second grade of clarity. Finally, from the use of "vinegar" in definitional propositions like "vinegar is diluted acetic acid" and "vinegar is sharp to taste," I can derive a list of conditional propositions which indicate what to expect from actions upon, and interactions with, this concept. So, for instance, "vinegar is acetic acid" would lead me to form the expectation that "If vinegar is acetic acid, then if I dip litmus paper into it, it will turn red." Having a list of conditional propositions like this, which express the differences this concept can make to expected experiences, allows me to achieve the highest grade of clarity about that concept. This third and final grade of clarity is the earliest statement of what we now know as the pragmatic maxim; it is the crux of Peirce’s early theory of pragmatism.

It should be clear that Peirce’s pragmatic maxim accords with his scientific inclinations. For Peirce, understanding the practical upshot of our concepts means exploring and experimenting upon the conditional hypotheses that we formulate with them. This not only reflects his broader notion of philosophy as a practical laboratory science, but also informs our conception of Peirce’s pragmatic maxim, as it is expressed in "How to Make Our Ideas Clear," as an account of meaning. The meaning of a concept is expressed by the list of conditional hypotheses that it generates. Interestingly, this seems to generate an account of meaning with two main elements: use and understanding.

The use element of the pragmatic maxim as an account of meaning is apparent from the meanings of the conditionals generated with the maxim. For instance, the meaning expressed by conditional statements about "vinegar" are not strictly about that concept considered in isolation. Rather, they provide the meaning for propositions containing the concept, such as "vinegar is diluted acetic acid," or "vinegar is sharp to taste." These conditional statements concern the practical experimental upshot of these propositions, rather than of the concept abstracted from them. This seems to generate meaning for concepts as they are used in sentences and propositions. It also makes the account of meaning an account of meaning for whole sentences, etc.

The second element of the pragmatic maxim as an account of meaning is understanding. We can see that it is the possibility of our understanding the outcome of taking a hypothesis to be true (in the form of conditional statements) that expresses the meaning of a concept. Since a meaningful statement is one for which we can derive practical and experiential consequences, our understanding, or grasp of those consequences, is our understanding or grasp of the meaning.